I've seen a few posts similar to this problem but I don't know if they're exactly the same. I need to record some voice chat sessions, specifically using Steam chat which has no record function. I've managed to set my computer & Audacity to use 'stereo mix' as the mic input and I've set the computer's mixer to 'Listen to this device' for my microphone. I'm now successfully hearing both my own voice and also whatever's playing through my headphones.However, when I now click to start recording in Audacity, it won't work, giving me the 'Error while opening sound device' message. I've seen threads where people haven't been able to do this because their computer doesn't support enough sound channels or something, but if I can hear both what's going into my mic and coming out of my headphones right now, why can't I just record it? If I can, how do I do so?